Causes of oil leakage in hydraulic cylinder of excavator and precautions

Oil cylinder is a very important object in the hydraulic system. Once the hydraulic cylinder of excavator leaks oil, it will lead to the phenomenon of slow lifting and powerless digging, which will seriously affect the working efficiency! What should we pay attention to when using excavators to avoid oil leakage from hydraulic cylinders?

I. external leakage

1. The seal between the extension end of the piston rod and the piston rod is damaged, mostly due to the roughening of the piston cylinder, but also due to aging.

2. Cracking of oil inlet and outlet pipe joints of oil cylinder will also cause leakage of hydraulic cylinder

3. Oil leakage caused by defects on the excavator cylinder body or cylinder end cover.

4. The piston rod is pulled, grooved, pitted, etc.

5. The deterioration of lubricating oil causes the temperature of oil cylinder to rise abnormally, which causes the aging of sealing ring.

6. The oil leakage is often caused by the use of the oil cylinder beyond the pressure range of the excavator.

II. Internal leakage

1. The wear-resistant ring on the piston is seriously worn, which causes friction between the piston and the cylinder liner, and finally damages the cylinder liner, piston and seal.

2. The seal fails in long-term use, and the piston seal (mostly u, V, Y-ring, etc.) is aging.

3. The hydraulic oil is dirty, and a large number of impurities enter the oil cylinder to wear the piston seal to the point of damage, generally iron chips or other foreign matters.

Precautions for use of hydraulic cylinder

1. In normal use, we should pay attention to protect the outer surface of the piston rod to prevent the damage to the seal caused by collision and scratch. It is necessary to frequently clean the sand on the parts of the dynamic seal dust ring and the exposed piston rod of the oil cylinder, so as to prevent the dirt that is not easy to clean pasted on the surface of the piston rod from entering the inner part of the oil cylinder, thus causing damage to the piston, cylinder barrel or seal.

2. During normal use, pay attention to check the connection parts of each thread, bolt, etc. frequently, and fasten them immediately if they are loose. Because the looseness of these places will also cause oil leakage of hydraulic cylinder.

3. Regularly lubricate the connection parts to prevent corrosion or abnormal wear under oil-free condition. Especially for some parts with corrosion, it should be handled in time to avoid oil leakage of hydraulic cylinder caused by corrosion.

4. During normal maintenance, the hydraulic oil shall be replaced regularly, and the filter screen of the system shall be cleaned in time to ensure the cleanness of the hydraulic oil, which is also very important for prolonging the service life of the hydraulic cylinder.

5. Each time we use the excavator, we need to carry out a full extension and full contraction test run for 3-5 strokes before working. The purpose of doing this is to exhaust the air in the system and preheat the systems, so as to effectively avoid the existence of air or water in the system and gas explosion in the cylinder block, which will damage the seals and cause internal leakage of the cylinder.